The elevator support means monitoring device is fixedly installed in an elevator installation or able to be installed for temporary use. The elevator installation consists substantially of a car which is connected with a counterweight by way of the elevator support means. The car is moved along a substantially vertical car travel path by means of a drive which selectably acts on the elevator support means, directly on the car or directly on the counterweight. The car travel path is usually integrated in a shaft in a building and in that case bounded by shaft walls, shaft ceiling and shaft base. The car travel path can also be attached to a building or building structure, wherein parts of the shaft walls, shaft ceiling and shaft base are eliminated or do not have to be defined by solid materials. In this connection, the shaft then substantially corresponds with the space which is determined by the movement and arrangement of elevator components as well as by requisite safety distances and safety spaces. The shaft or the shaft walls is or are provided with accesses which selectably enable access to the car.
The elevator support means thus supports the car and the counterweight. These elevator support means are frequently not only subjected to supporting forces, but also transmit, for example by means of traction, a drive force from the drive to the car or the counterweight.
The elevator support means are frequently provided with load-bearing tension carriers which are enclosed by a traction-optimizing casing. The elevator support means is subjected to wear and abrasion. Elevator support means accordingly have to be monitored with respect to the length of use thereof so as to preclude failure of the elevator support means or to be able to replace the elevator support means in good time.
Monitoring methods of that kind can be carried out manually, for example by visual checking. However, the elevator support means can also be provided with optical wear markings such as disclosed in, for example, EP 1275608.
Other methods provide a magnetoinductive check such as proposed by, for example, Prof. Dr. Ing. K. Feyrer in his publication with respect to measuring and monitoring of running wire cables, ISBN 3-8169-1481-0; Chapter 7. Many other methods are known in elevator technology. A further monitoring method, such as proposed by way of example in WO 00/58706, measures a resistance of tension carriers and correlates it with the load-bearing capability of the support means. Other methods such as disclosed in, for example, EP 0731209 use indicator strands which are admixed with the tension carriers and twisted therewith. Tearing of an indicator strand indicates increasing ageing of the support means.